A glass substrate used in an outermost layer of a cell phone, a tablet PC or a navigation device has various advantages such as a small coefficient of linear expansion, excellent gas barrier property, high light transmissivity, surface flatness, excellent heat resistance, chemical resistance, etc. However, a glass substrate has disadvantages in that it is vulnerable to impacts to be easily broken, and is heavy due to high density.
In accordance with recently increased interests in a liquid crystal display or an organic light emitting diode display, a flexible display, an electronic paper, research into a technology of substituting these glass substrates with plastic substrates has been ongoing.
Incidentally, a methacrylate-based resin is one of the most widely used transparent resins due to excellent transparency and processability, excellent balance in mechanical physical properties, and lower price as compared to a polycarbonate resin. However, the use of the methacrylate-based resin has not been employed in elements of a display such as a light guide plate, a diffusion plate, etc., or in elements especially requiring heat resistance such as a lighting apparatus, an optical lens, etc.